Ilkay Gundogan opened the scoring after eight minutes, before Phil Foden curled in a superb second inside 15 minutes.
Pep Guardiola‘s men struck the woodwork three times before the interval, before Erling Haaland coolly slotted us further ahead shortly before the hour mark.
McAtee was introduced from the bench and made an instant impact, firing in our fourth after a clever pass from Foden.
The Academy graduate almost doubled his tally shortly after, but saw his effort well saved by Slovan Bratislava goalkeeper Dominik Takac.
“I’m buzzing,” declared McAtee after the game. “I could have got another one like five minutes after.
“I’m over the moon. I think this is what every kid dreams of, so it’s definitely a dream come true.”
The 21-year-old made his senior debut back in September 2021 before spending two seasons on loan with Sheffield United.
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However, he has now been integrated into the first-team squad for this campaign by Guardiola and is set to continue getting valuable minutes ahead of a busy fixture schedule.
“It’s good to be back,” he said. “Obviously, it was a tough year last year for me personally.
“It’s good to be back and learning off the best players in the world in my opinion.”
The victory means City have four points from two matches in the competition’s new league phase, with six fixtures remaining.
